We have a ZK project that uses Eclipse and SVN for version control. Our ZULs get checked-in to the SVN repository. When I select (right-click) the file in my project and select Team > Show History. It lists the revisions made to the zul file. When I choose to open a previous revision to see its contents (not replaceing the current version, just open to view), the following exception occurs: ("Could not open the editor: An unexpected exception was thrown."

java.lang.NullPointerException
at org.zkoss.eclipse.editor.core.model.ZulContext.reconcileProjectContext(ZulContext.java:382)
at org.zkoss.eclipse.editor.core.model.ZulContext.inputDocumentChanged(ZulContext.java:320)
at org.eclipse.jface.text.TextViewer.fireInputDocumentChanged(TextViewer.java:2888)
at org.eclipse.jface.text.TextViewer.setDocument(TextViewer.java:2937)
at org.eclipse.jface.text.source.SourceViewer.setDocument(SourceViewer.java:640)
at org.eclipse.jface.text.source.projection.ProjectionViewer.setDocument(ProjectionViewer.java:376)
at org.eclipse.wst.sse.ui.internal.StructuredTextViewer.setDocument(StructuredTextViewer.java:805)
at org.eclipse.jface.text.source.SourceViewer.setDocument(SourceViewer.java:588)
at org.eclipse.ui.texteditor.AbstractTextEditor.initializeSourceViewer(AbstractTextEditor.java:4030)
at org.eclipse.ui.texteditor.AbstractTextEditor.createPartControl(AbstractTextEditor.java:3558)
at org.eclipse.ui.texteditor.StatusTextEditor.createPartControl(StatusTextEditor.java:54)
at org.eclipse.ui.texteditor.AbstractDecoratedTextEditor.createPartControl(AbstractDecoratedTextEditor.java:440)
at org.eclipse.wst.sse.ui.StructuredTextEditor.createPartControl(StructuredTextEditor.java:1508)
at org.zkoss.eclipse.editor.wst.ZulTextEditor.createPartControl(ZulTextEditor.java:258)
at org.eclipse.ui.internal.EditorReference.createPartHelper(EditorReference.java:670)
at org.eclipse.ui.internal.EditorReference.createPart(EditorReference.java:465)
at org.eclipse.ui.internal.WorkbenchPartReference.getPart(WorkbenchPartReference.java:595)
at org.eclipse.ui.internal.EditorReference.getEditor(EditorReference.java:289)
at org.eclipse.ui.internal.WorkbenchPage.busyOpenEditorBatched(WorkbenchPage.java:2945)
at org.eclipse.ui.internal.WorkbenchPage.busyOpenEditor(WorkbenchPage.java:2850)
at org.eclipse.ui.internal.WorkbenchPage.access$11(WorkbenchPage.java:2842)
at org.eclipse.ui.internal.WorkbenchPage$10.run(WorkbenchPage.java:2793)
at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:70)
at org.eclipse.ui.internal.WorkbenchPage.openEditor(WorkbenchPage.java:2789)
at org.eclipse.ui.internal.WorkbenchPage.openEditor(WorkbenchPage.java:2773)
at org.eclipse.ui.internal.WorkbenchPage.openEditor(WorkbenchPage.java:2756)
at org.tigris.subversion.subclipse.ui.actions.OpenLogEntryAction$1.run(OpenLogEntryAction.java:56)
at org.tigris.subversion.subclipse.ui.repository.RepositoryManager.run(RepositoryManager.java:375)
at org.tigris.subversion.subclipse.ui.actions.SVNAction$1.run(SVNAction.java:226)
at org.tigris.subversion.subclipse.ui.actions.SVNAction$2.run(SVNAction.java:235)
at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:70)
at org.tigris.subversion.subclipse.ui.actions.SVNAction.run(SVNAction.java:232)
at org.tigris.subversion.subclipse.ui.actions.OpenLogEntryAction.execute(OpenLogEntryAction.java:35)
at org.tigris.subversion.subclipse.ui.actions.SVNAction.run(SVNAction.java:56)
at org.eclipse.ui.actions.ActionDelegate.runWithEvent(ActionDelegate.java:70)
at org.eclipse.ui.internal.PluginAction.runWithEvent(PluginAction.java:241)
at org.eclipse.jface.action.ActionContributionItem.handleWidgetSelection(ActionContributionItem.java:584)
at org.eclipse.jface.action.ActionContributionItem.access$2(ActionContributionItem.java:501)
at org.eclipse.jface.action.ActionContributionItem$5.handleEvent(ActionContributionItem.java:411)
at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:84)
at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1053)
at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:4165)
at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3754)
at org.eclipse.ui.internal.Workbench.runEventLoop(Workbench.java:2701)
at org.eclipse.ui.internal.Workbench.runUI(Workbench.java:2665)
at org.eclipse.ui.internal.Workbench.access$4(Workbench.java:2499)
at org.eclipse.ui.internal.Workbench$7.run(Workbench.java:679)
at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:332)
at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:668)
at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:149)
at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:123)
at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:196)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:110)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:79)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:344)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:179)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:622)
at org.eclipse.equinox.launcher.Main.basicRun(Main.java:577)
at org.eclipse.equinox.launcher.Main.run(Main.java:1410)
at org.eclipse.equinox.launcher.Main.main(Main.java:1386)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at com.genuitec.pulse.eclipse.launcher.Main.main(Main.java:110)